One explanation: When the PIC port pins are used as inputs, the the impedance is very high. You need a 10K Ohm resistor connected between each input pin and + 5 volts. A wire goes from each pin to each switch contact, and the other side of the switch contact goes to ground. When the switch is closed, the pin goes to ground. When the switch is open, the resistor pulls the pin to +5 Volts. Without the resistor to +5, the pin floats to an unknown voltage, until you touch it with you hand, then it sorta works. You probably don't need the resistor between the pin and the switch. I have never lost a PIC when the switch was closed, and the pin was set to an output, and set high. Makes a nice heater in the winter :) If you are going to be touching the board when it is running, be sure to set those pins to inputs (or outputs as the case may be) quite often, the TRIS registers are known to change values on their own with nearby static discharge. Regards, Ron Fial At 03:26 PM 10/15/99 +1000, you wrote: >>>> Hi all, I am having some funny things happen with veroboard ciruit I have made to learn PIC's. I have wired up 4 Leds off porta and eight dip switches off portb. The dip switches I have a 10k resistor in series with them in cases of accidently setting the port to output and shorting the dirver. The circuit sort of works as long as you put your hand on the vero board, else things go a bit funny. When I first built the circuit I put the dip switch common to V+. This did not work. So now I have it at V- and it sort of works? Q. what is the correct way to read the status of the port into a register. Thanks in advance. Mathew Cohen mmjcohen@nsw.bigpond.net.au